Self-anchoring nut



Sept- 9, 1941 .1. P. BURKE 2,255,650

SELFANCHORING NUT Filed Feb. 3, 1940 Patented Sept. 9, 1941 SELF-ANCHORING NUT James P. Burke, Knoxville, Tenn., assignor to Bert L. Qnarnstrom and F. L. McLaughlin, both of Detroit, Mich.

Application February a, i940, serial No. 317,092

(cl. ss-sz) 2 Claims.

This invention relates to self clinching or crimp nuts and has for its primary object to provide a nut adapted to be inserted into an opening in a supporting member and having laterally expansible means adapted to be projected laterally outwardly therefrom, when a bolt is tightened therein, for preventing withdrawal of the nut from the opening.

More specically, the main object of the invention is to provide a nut of this character which is formed of a single piece of sheet metal. In this respect a single piece of sheet metal is formed by conventional metal pressing and punching machinery to provide an abutment portion, a laterally expansible portion and an internally threaded portion, the internally threaded portion being connected to the expansible portion by a conical portion which acts in the presence of compression forces between the screwthreaded and abutment portions to cause lateral expansion of the expansible portion,

Another lobject is to provide a nut of -the type above mentioned having snap fastener means by which It may be retained in an opening while the member which supports it is being transported from place to place.

Otherobjects and advantages will become more fully apparent as reference is had to the accompanying drawing wherein my invention is illustrated, and in which Fig. 1 is a side elevation of a nut,

Fig. 2 is a vertical cross-section,

Fig. 3 is a plan view,

Fig. 4 is a cross section illustrating the nui-I in use,

Fig. 5 is a section illustrating thevnut functionl ing in a manner similar to a rivet, and having article supporting means formed integral therewi r Fig. 6 isa cross section illustrating an alternate mode of using the nut, and

Figs. I and 8 are elevations illustrating alterna- I tive snap fastener means.

More particularly, I designates the abutment portion of the nut, having ahollow, substantially square portion 2 arising therefrom. ,It is not essential that this portion be square, and it is shown as square merely by way of example. It is essential, however, that it be other than round shape so that the nut will not turn when it is inserted in an aperture in a supporting member.

The portion 2 is weakened by removing portions thereof to form holes 3. In the case of a square nut such as shown it is preferred that these holes 3 be formed at the corners thereof as shown.

The portion 2 constitutes a laterally expansible means, and is connected by a conical portion 4 to an internally threaded portion 5. In forming the nut of sheet metal, the blank is rst extended to form the portion 4 and is then compressed .by a bump-back step to form the relatively smaller cylindrical portion 5. This method of forming the nut has an advantage in that the "bump-back results in a thickening of the walls of the portion 5, and a partial thickening in the conical portion 4. This provides an abundant thickness for the threads 6, which are formed by a subsequent tapping operation, and also provides for strengthening the upper region of the conical portlonl. The conical portion 4 gradually thickens upwardly and its weakest point is at the juncture with the portion 2.

As shown in Fig. 4, the nut may be placed through apertures in two sheet metal members 1, a bolt 8 may be inserted therein, by tightening the bolt 8 the conical portion 4 forces the portion 2 outwardly laterally, and the portion 2 will prevent withdrawal of the nut from the openings.

Inasmuch as the nut and assembly shown in Fig. 5 is similar to that above described it is generally designated by the numeral 9. It illustrates that the nut may be employed in the nature of a rivet, for securing the two members 'la together when the bolt which collapsed it is removed. Formed integral with the nut 8 is a retainer I0 which may be employed for supporting a cable I I or any other similar article.

The nut I2 shown in Fig. 6 is identical to the nut first described. In this case, however, the nut is retained upon one supporting member I3 and the other member I4 is secured thereto by the bolt I5. 'This illustrates that the nut may be used in such manner that the two connected members may be separated by removing the bolt, which is not the case as shown in Figs. 4 and 5.

In order that the nut may retain itself in an aperture in a supporting member snap fastener means is provided. As shown in Fig. 7 this means may be formed by shearing two of the side portions of the portion 2a and bending them outwardly to form spring fingers I6. These ngers I 6 compress when the nut is inserted in an aperture in a supporting member and then snap outwardly to engage the inner face of the supporting member. An alternative form of snap fastener means may be provided by forming the sides of the portion 26 shown in Fig. 8 with outwardly projecting spring fingers I1.

Although specic embodiments oi the invention have been illustrated and described. it willbe understood that various changes may be made within the scope of the appended claims without I converging upwardly Yfrom said expansible portion, and an internally threaded portion integral with and arising from said frusta-conical portion, two of the sides of said expansibie portion being severed and bent outwardly to constitute snap fastening spring lingers.

2. A nut comprising an abutment portion, a pair of parallel arms arising from said abutment, said arms being Joined at their outer ends by an integral substantially vfrusta-conical portion, an

internally threaded tubular portion integral with` the outer and smaller end of said i'rusto-conioal portion, and a pair of parallel arms arranged at right angles to the first named arms, saidsecond pair o! armsbeing integrally connected with said misto-'conical portion and extending therel a direction both radially outwardly and from i toward id abutment portion. v t JAMES P. BURKE. 

